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J078-/S 



AUG 1 21938 




Architectural Concrete 
SMALL BUILDINGS 



Architectural Concrete 




SMALL BUILDINGS 



nOMMEhniAL-IMJUSThlAL-miiLK; 



l'uhlixh.,1 in PORTLAND CEMENT ASSOCIATION 
33 West Brand Avenue, Chicago, Illinois 




i.V. S. Post Office, Stephenville, Texas. Mark Lemrrum, architect, Dallas; Lundburg and Richter, contractors, Liberal, Kansas. 



'The building shall nut depend fur its impressiveness upon anything that is perishable/'— Ruskin 



FHHF WflRD Careful P lannin g> attractive 
I UllL f T IJIILI design an d workmanlike con- 
struction are essential in the small store, factory or 
village fire station just as they are in a monumental 
post office or large city school. Simply because a 
building is small is no reason why it should just grow 
up like Topsy. 

The Main Streets of the country are largely made 
up of one and two-story buildings housing but a single 
commercial or industrial enterprise. Individually they 
may not seem important nor of concern to others than 
the owner or occupants, but collectively they make the 
tiny village, the middle-size town and the big city. 
The appearance of the whole community depends 
upon the separate units which constitute it. 

Aside from individual and civic pride in the fine 
appearance of one's property or community there is 
the more mundane but equally important considera- 
tion of the investment value of the well-built, per- 



manent, attractive building. Customers are drawn to 
the store that looks inviting, to the bank that reflects 
its sound conservative policy in the substantial appear- 
ance of its place of business, and even the corner gas 
station that radiates efficient service in every line of the 
structure attracts trade from the less pleasing establish- 
ment across the corner. Moreover, the initial cost of 
such buildings is often no greater than that of their 
less attractive neighbors and, when constructed of 
durable firesafe materials properly used, the mainten- 
ance and insurance costs that go on throughout the 
life of a building may be reduced to a minimum. 

This booklet is written to assist the building pro- 
fession and owners to secure full value from the use 
of architectural concrete in small buildings by pre- 
senting a few examples and offering some suggestions 
about the use of the material. 

Vtirtlund (,'emenf Association 



Architectural Concrete For Small Buildings 



SECTION 1 — ARCHITECTURAL DESIGN 



MUCH has been written on the fundamental princi- 
ples of architectural design. It is not intended in 
this booklet to enlarge upon or even discuss the applica- 
tion of those principles to buildings in which concrete is 
the architectural medium. As far as design fundamentals 
are concerned, there is no essential difference between the 
concrete building and buildings constructed of other 
materials. It is true that one material may give greater 
freedom to the designer to exercise his imagination than 
does another material which may have structural limita- 
tions or limitations of form and texture. But, in the 
sense that architectural design involves consideration of 
purpose and function, mass and line, rhythm and har- 
mony, the problem presented by the architectural con- 
crete building is in no way unique. 

There is likewise no vast difference between the design 
of a small building and a large one. In the broad sense, 
architecture embodies and makes use of most of the fine 
arts and many sciences, combining them into a physical 
structure that meets the practical demands of supporting 
loads and affording shelter while satisfying certain 
esthetic requirements. Obviously, if the small building 
is to be pleasing to the eye, is to fulfill the requirements 
of good architecture, then the same application of the 
arts and sciences must be 
made as in the design of 
more pretentious buildings. 

Primarily it is in the de- 
tails that architectural con- 
crete differs from other ma- 
terials. How to obtain de- 
sired form, texture and 
color; what can be done 
most appropriately, readily 
and economically? It is in 
the answers to these ques- 
tions that the designer is 
vitally concerned with the 
architectural medium, so 
that which follows will be 
devoted only to those de- 
tails influenced by the use of 
concrete as a finish material 




Surface 

Whether a building is constructed of brick, stone, terra 
cotta or concrete, the surface characteristics of the mate- 
rial have a pronounced influence on the designer's con- 
ception of how the structure should appear. Having 
visualized the lines, proportions and masses of the build- 
ing, translation of the mental picture into a satisfying 
reality requires a surface in harmony with the conceived 
design. The rough, coarse, rugged texture suitable for a 
building of large scale and normally viewed from a dis- 
tance would obviously be out of keeping with a ladies' 
apparel shop or beauty salon done in delicate detail and 
situated at the sidewalk line. 

A variety of textures ranging from a perfectly smooth 
surface without joint lines and no trace of the nature of 
the forming material, to the roughest texture showing an 
exaggerated impression of the grain of the form lumber, 
is possible in architectural concrete. If the texture 
selected is in harmony with the design, then it will look 
well whether smooth, rough or between the two ex- 
tremes. The designer should be familiar with the variety 
of textures possible and just how he may expect them 
to appear in the finished job. 

Some of the many pos- 
sible surface textures in 
architectural concrete are 
illustrated and the methods 
of producing them are 
briefly described in Figs. 3 
to 6*. While the number of 
types of surface finish is 
limited only by the inven- 
tiveness of the architect 
and the skill of the con- 



Fig. 2. Radio transmitter station KFPY, Spokane, 
Washington. Rigg and Vantyne, architects; Allotvay 
and Qeorg, coyitractors, 



*References will be made in foot- 
notes and throughout this book- 
let to other publications issued 
by the Portland Cement Associa- 
tion containing additional per- 
tinent information which will be 
sent free upon request. Addi- 
tional textures are shown and 
described in "Concrete Informa- 
tion — Textures — AC 11." 



Page 3 











Fig. 3 (a) 







Fig. : 




Fl Z I 



Fig. 3. Board-marked surfaces, painted and unpainted, offer a 
wide variety of textures from which to select the most appropriate 
for the style of architecture being considered. Three such tex- 
tures are shown: (a) formed with vertical grain square-edged 
fir hoards uniformly sized for thickness; (b) a slightly rougher 
texture produced with the same kind of lumber except boards 
of various thicknesses were selected to accentuate the jointing; 
(c) surface showing characteristic grain marking and occasional 
impression of knots left by square-edged yellow pine boards. 
The right-hand side of each picture shows the surface after 
applying two coats of cement paint. Smoother textures, but still 
showing faint traces of the joint lines between the sheathing 
boards, are obtained by using dressed and matched lumber. 



tractor to find a means to execute the design, unusual 
or "trick" finishes should be avoided. Standard sur- 
faces made with ordinary form boards, plywood or 
Presdwood and left in the natural finish revealed 
when the forms are stripped are suitable for most archi- 
tectural styles. The surface may also be painted where 
a color other than that of natural concrete is desired or 
a light stucco spatter dash may be applied. 

There is no objection to a rubbed finish when an abso- 
lutely smooth surface is desired, but the work must be 
properly done. It is not good practice to work up a thick 
paste on the surface which is left there, and allow it to 
dry. Even though this finely ground materialis kept wet 
to allow it to reset, crazing and subsequent scaling may 
result. The paste that is worked up on the surface must 
be removed as described in the caption of Fig. 5, leaving 
only a very thin film on the surface. 

Regardless of the surface texture chosen, it is advisable 
to construct a demonstration panel using a part of the 
basement wall or some other unexposed wall to deter- 
mine definitely that the selected surface is just what is 
desired, and that the contractor is executing it properly. 
Such a demonstration panel should be constructed in 
everv detail exactly the same as the exposed walls above 
grade will be built. Not only should the forms be the 
same but the concrete should be of the same mix and 
consistency. The place to experiment is below grade- 
not above. 



Construction Joints 

The technique of construction should always be taken 
into consideration in the design of any building, regard- 
less of the building material. Just as the mortar joints 
and brick courses in a brick masonry building are an 



Fig. 4. Rjihbed surfaces present several additional textures\having various degrees of smoothness; (a) slightly sandy texture produced 

:cd concrete wall with a wood float one day after placing; (b) smoother finish produced by rubbing a dry 
1 stone after concrete has thoroughly hardened. The right-hand side of each picture shows the surface 
cement paint 



Fig. 4 iu 



Fig. 4 (b) 





a f h f f t t 

Fig j / /. in tlu- finishing of d wcl i ul 

nto the holes u ith a grcd 
> ubbi 

■:!\ U ith ,1 mom,/ //. 



inevitable pan oi thai type ol structure and arc taken 
into account in the layoui ol fenestration and other 
. tlu- construction joints in an architectural 
huiUuik; an essential pare ot the construction 
Hie concrete in walls ol only the smallest building 
he placed in one continuous operation Almost always ii 
is n to provide horizontal construction joints 

and occasionally vertical joints will be needed 

Since construction joints are inevitable they should he 

taken into consideration m the design and should he 

definitely located on the drawings hv the architect and 

no change should be made without his approval When 

locating joints, a reasonable placing rate should be t 
sidcred, generally not to exceed 2 feet in hour and a lite 
of about 6 feet b etw e en iomts should be a maximum 

Is 1 rule, convenient locations tor |omts will he at the 
water table, at the window sills and heads and occasion 
all} at the Boot levels, although the latter is not so Jk 
able, especially il the spandrels are to he left with 1 
smooth surface 



rusti 

Vcri 

in u h 



pr 1 



6 (a) 







pre- 
j 
lum- 



Spandrels 

The spandrels in a building are important elements in 
the architectural design. They afford an opportunity for 
decorative treatment, and proper detailing will do much 
to enhance the appearance of the building. As noted in 
the discussion of construction joints, it is sometimes 
accessary to locate a joint at the floor level, which will 
often be about the mid-height of the spandrel. Under 
such circumstances it is highly desirable to provide some 
horizontal architectural detail at that level at which to 
stop the placing of concrete. If this can not be done con- 
veniently, an ornamented spandrel in which the otherwise 
plain surface is broken up into a design or pattern will 
aid greatly to make the joint inconspicuous by providing 
a play of light and shadow. 

In urban communities it is inevitable that the moisture 



ing, others prefer to prevent it if possible or to make it 
less noticeable by some device. 

Projected window sills will help prevent moisture 
streaking to some extent by causing the trickles of water 
to drip free of the wall. The nose of the sill should, of 
course, be provided with a drip. Sills of this type may 
be precast and set after the rest of the wall is completed, 
or they may be cast in place after the concrete in the 
spandrels and jambs has hardened.* 

When flush sills are used or even with projected sills, 
apparent discoloration can be minimized readily in archi- 
tectural concrete by taking advantage of light and 
shadow. For example, a spandrel with vertical flutes will 
not appear to be discolored by water streaks, while they 
would be quite noticeable on a plain, smooth surface. 
The moisture will tend to follow the back of the flutes, 
which are in shadow, while the outer surface is in high- 



Fig. 7. This unit of Safeway Stores, Inc., Spokane, Wash., desigyied by Rigg and Vantyne, architects, and constructed by Peter 
Y ou - xg clapboa g The effect was produced by overlapping the S-in.-itidc sheathing boards. Walls are 

buff-colm it paint, white fluting in pilasters is accentuated with a contrasting color. 




which collects on windows will trickle down over sills 
laden with soft coal soot. This dirty water will then run 
down over the spandrel below. It is not the water that 
rushes down the window pane during a hard rain that 
causes streaking and discoloration of the wall surface, 
but these small trickles of soot-laden moisture. While 
this natural aging and discoloration is not considered by 
many CO be detrimental to the appearance of the build- 



light Any kind of decoration that breaks the surface into 
a pattern of raised and incised areas will create a design 
of light and shadow that will obscure moisture streak- 
ing.** 



* See "Concrete Information — Windous — AC 6." 

** See "Concrete Information — Spandrels — AC 9" for additional 
illustrations and construction details. 



Page 6 



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( >rn mil 1 1 r m 1 1 , enhai 

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Fig. 10. Variety oj 
tures lends interest to 
Shopping News build- 
ing, Long Beach , 
Calif., designed by 
Miller and Qibbs, 
architects, and built by 
J. E. Burrell, con- 
tractor. Plywood with 
smooth joints was used 
for the spandrel forms, 
while slight irregu- 
larity of the joints be- 
tween plywood panels 
on the parapet 
permitted to produce in- 
teresting contrast. An 
even greater contrast is 
obtained by using 
rough-sawed sheathing 
with chamfered edges 
for the wall bet, 
spandrel and par,. 
Construction joints at 
sill and head of win- 
dows are obscured by 
the projecting bands. 



SECTION II-SPECIFICATIONS 



SECOND only in importance to an adequate set ol 
pl ai >>n It is the written basis 

Hiding between the architect, contractor and 
bow the construction of the job is to be 
■at and what results maj reasonably be expected 
n should he made positive 
^nd defio 

The tor the architectural concrete work 

1*11 build; not differ materially from that 

KCCpt perhaps, because of the size 
a rk'< l -in small job all the possible 

be required for that building 
/en a small structure may invol 
iscency o( design untitled and lined 
iste molds and metal forms All the 
materials and careful workmanship 
thai Drill CO the large job are equally essential to 

-mall one and they should be set forth in the specifi- 
cation The principal subjects that should be included in 
unal concrete specification are discussed in the 
j paragraphs. 



Materials 

The cement should be specified to be of American 
manufacture conforming to the standard specifications 
of the American Society for Testing Materials for stand- 
ard portland cement or high early strength portland 
cement. By requiring that the cement be delivered to the 
job in sacks bearing the brand and name of the manu- 
facturer, conformity with the specification may be assured 

Fine aggregate is usually natural sand, although arti- 
ficial sand made of crushed limestone is sometimes u 
If the latter is permitted it should be definitely stated 
that the artificial sand shall be manufactured specifically 
as fine aggregate for concrete Ordinar. 

nings arc not satisfactory. Artificial sand m 
form with the grading required for natural sand and 
should be considered acceptable only i( a con 
satisfactory workability can be made with it 

A uniform gradation of the fine aggregate 95 per 
cent of which should pass a ! 
required It is important that the fine aj Jin 



Page 8 





*s 



JiJPHI 




Tl 



Fig. 11. Construction joints need not be conspicuous even in large, smooth areas when properly constructed. Simplicity, 
unmarred smooth surfaces and floiving lines characterize the Teche Qreyhound Bus Depot, New Orleans. Diboll, Boettner and 
Kcsscls, architects; Caldwell Bros, and Harte, contractors. 



a certain amount of material that will pass a No. 50 sieve 
in order co produce a workable mix and one that will 
not "bleed." By bleeding is meant the accumulation of 
water at the top of the concrete being placed, which is 
the cause of sand streaking. This can be prevented very 
largely by being sure that at least 10 per cent of the 
sand will pass a No. 50 sieve and preferably more, up 
to a maximum of 30 per cent. The specifications should 
also require even a small amount of material to pass the 



No. 100 sieve. From 3 to 7 per cent is desirable. 

Crushed stone or gravel are most commonly specified 
as coarse aggregate for architectural concrete, although 
other inert materials are sometimes used. There is a mis- 
taken idea that a rather small, coarse aggregate is needed 
for architectural concrete in order to produce sharp 
arrises and details. Such is not the case and concrete made 
with a coarse aggregate, all of which will pass a J^-in. 
sieve, will require about l A sack of cement more per 



Fig 12. Horizontal rustications at fairly close spacing make it possible to place concrete in relatively small quantities, which 
is conducive to good construction. Architects Maurer and Maurer used this device which also emphasizes the horizontally 
of the Long Beach Country Club, Long Beach, Indiana. Tatus and Nelson were the contractors. 




Page 9 




Fig. 13 The small relatively un ted building when well designed and constructed is a business asset. Typical of 

modern service stations that attract business is the Shell Oil Company of Canada station in Toronto, designed byK Q Blackburn, 
clue] 1 I built by S. McLachlan, contractor 



cubic yard than one made with 1 ':-in- top-size rock to 

luce a concrete of the same degree of workability. 
This simply adds unnecessarily to the cost of the job, 

job it is advisable to require 95 per 

t of the coarse aggregate to pass a lW-m sieve and 

be graded uniform h down to the No. 4 sieve size with 

nt passing that sieve Some tolerance of 

ermediate sizes is of course nccessarv as, for example, 
a ran J5 to - per cent passing a J^-in. sieve and 

■li 1 to ^ per cent passing a : > -in sieve is acceptable. 
t )nce a grading between these limits is accepted however, 



a greater variation than 10 per cent should never be per- 
mitted in the amount passing any sieve size, otherwise 
it will be very difficult to produce uniformly workable 
concrete. 

It is usually recognized that the mixing water must be 
clean and free from injurious amounts of alkalies, vege- 
table matter and other impurities, but it is advisable to 
include such requirements in the job specification. 

Only intermediate grade new billet steel or rail steel 
deformed bars or cold drawn steel wire mesh are suitable 
for concrete reinforcement. Sucker rods used in the oil 



is Warei ornamented simply with pilasters and rustications made by -nailing slightly 

■ County }<>rcc> and built by U7V1. 



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SUMNER CO. WAREHOUSE 









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I. 



,_jl 



^IV-&-Ni_nA«4--- 



HIII:«=*«l^:iJi:^'lW|.| ;- ;iHt :W M:i 




Fig. 25. Use was made of several types of ornament for Avon Theater, Boonville, N. Y. Fluting and interesting chevron device 
could be formed with wood, while medallion at top of pilasters and parapet detail would require plaster waste molds. H. Q. Rice, 
Rome, N. Y., was the architect and C. J. Burgess the contractor. 



fields, chicken wire, and similar substitutes should never 
be accepted under any conditions. The specifications 
should definitely require reinforcement bars or mesh to 
conform to the standard specifications of the American 
Society for Testing Materials. 

Storage of Materials 

The storage of materials is generally not a very serious 
problem on the small job because the quantities involved 
are not great. There is sometimes an inclination, how- 



ever, because the quantities are small, to be careless about 
protecting the cement from moisture and allowing the 
aggregates to become dirty. Cement undamaged by 
premature wetting and clean aggregate are essential for 
good quality concrete. The specification should require 
adequate protection. 

Forms 

The perfection of the finished concrete surface and 
details is the criterion of the quality of job and as the 



Fig. 16. Fluted pilasters contrast with the horizontal lines of the Animal Shelter, Memphis, Tenn. M. H. Furbringer, 
architect; M. Q. Ehrman, associate — WPA project. 







M 




I * 










Fig. iy. Modem as the radio is the transmitter station for 
KQQ, Spokane County, Wash., built by Alloway and Qeorg. 
The round, fluted corners of the building were formed with cor- 
rugated iron. 

to be sure all joints are properly made and pointed to 
prevent leakage. Leakage of forms is the worst obstacle 
to obtaining sharp corners. 

Douglas fir plywood H in- and K in- thick is very 
commonly used for form sheathing. Only plywood made 
with waterproof glue specifically for concrete formwork 
should be allowed. Ordinary plywood will not give a 
satisfactory job. The joints between adjacent sheets of 
plywood should be required to be backed solidly by nail- 
ing both edges to the same stud; otherwise there will be 
an offset joint. Close nailing, not over 8 in. apart, is 
essential for smooth joints. 

When forms are to be lined there is an inclination to 
spread the backing boards some distance apart. This prac- 
tice should be prohibited by the specification because it 
results in a wavy surface in which the impression of the 
sheathing boards is very noticeable. Square-edge lumber 
mav be used for backing, but T & G or shiplap is | 
era hie. 

Form liners should not be too thin. The specifications 
should require at least a %-in. Presdwood or J 4 -in. ply- 
wood lining, otherwise the joints in the backing will he 
noticeable in the finish sur! 

Forms for ornamental detail may be made ol wood or 
plaster and sometimes metal. If made ol wood only, 
No. 2, or better, Idaho white pine or equal should k 
permitted White pine is easily worked and as it does not 
swell and Wirp as other woods do, sharp edges ol detail 
are less likely CO be broken 

It the job Involves details made ol floral forms Ol 



largely 

hich the concrete 

. d [a ut riling 

I )oug 
Laid be permitted 
: to be lined with 
I imes a rough texture sur 
and flaws in the 

• •• cures 

• rds mav be used 
It i ) the 

• ads and 
■ 
J it will be CO I 
l 
: fiat the 
. 















Fig ig.l luted pilasters lend height to main building of the Sewage Disposal Playit, Vinton, Iowa. H. R^. Qrecn Co 
Cedar lydpids; E. B. Spencer, contractor, Waterloo. 



rounded and warped surfaces, plaster waste molds muse 
be specified Such molds should be required to be well 
reinforced with fiber and otherwise reinforced to prevent 
breakage 

Pointing of all joints in architectural concrete forms is 
important and should be required in the specifications 
and carefully observed by the inspector on the job. Wata 
putty, patching plaster or a mixture of equal parts of 
tallow and portland cement may be specified for pointing. 

Form ties ^\\n do much to make a good quality job or 
to ruin what otherwise would have been a good job. 
Too often specifications simply require the forms to be 
well tied together. This is not sufficient for architectural 



concrete. The type of tie muse be specified. Under no 
cumstances should wire or strap iron be permitted The 
tie used should be one that will leave the smallest ; 
sible blemish on the surface and positively must K 
no metal closer than \ l /i in. to the surface. Ties with 
lugs, cones, washers and other devices to act as spreaders 
that leave a hole larger than 7 > in in diameter or a de- 
pression at the surface that can not be patched should be 
definitely prohibited. 

Easy stripping of the forms is essential to prevent 
breaking corners or damaging the surface. Oiling of all 
forms should be required, but all excess oil should be 
. staining the concrete 




Fig. 20. Paneled 

drels, flu' and 

small 

details in th 

take this uarehou 5 

•itar- 
lum, Springfield, Mass., 
outojtheclass < 
storage buildings 
A/ ( }ray t architc. 










\m 







11. Simplicity of design with just enough ornamental detail make the Woolverton and CroshU garaze and salts room an 
do business. Located in Long Beach, Calif., the building u schilling and Schilling, architects. 



Reinforcement 

It ma en more important for the small job than 

mc to be specific about the cleaning, bending 
and placing of reinforcement, because this work is often 
done by inexperienced laborers. No reinforcement should 
be permitted closer than 1 : j in to the surface of the 
con : the practice of driving nails into the front 

form for the purpose of supporting the reinforcing in any 
t must be prohibited 

Proportioning Concrett 

.ontrol ol co insure uniform:* 

the and particularly a uni : work- 

under which the concrete i 



be placed, is cspccialU essential for architectural concrete 
work Weight measurement of the aggregates rather 
than volume measurement will aid greatly in securing 
accurate control of the concrete mixture, because varia- 
tions in moisture content of the sand affect the weight 
but little, but materially affect the volume due to bulk- 
ing It is, therefore, advisable to require weight batching. 
Aside from giving more accurate control, it usually re- 
sults in a saving to the contractor 

Durability of the concrete is more vital than strength 
in an architectural concrete job, particularly in a small 
building, because the stresses are low As far as strength 
is concerned y l A or S gallons of water per sack of cement 
might be used with even less than 5 sacks of cemer/ 
the yard Such concrete, however, would not give satis- 
factory surfaces nor would it be sufficiently dense and 



Page 14 



impervious for the exposure to which it is subjected. To 
insure adequate durability, not over 6>2 gallons of water 
per sack of cement and not less than 5^ sacks of cement 
per cubic yard should be allowed if the building will be 
subject to freezing and thawing. In the south and along 
the west coast a half gallon more of mixing water to 
a sack of cement and a minimum cement content ot 
5 ' 4 sacks to the cubic yard are satisfactory. 

It is advisable to specify the slump of the concrete as 
a guide to a satisfactory degree of workability. The 
slump should be under 6 in. for hand placing and less 
than 4 in. if vibrators are used, otherwise segregation 
and sand streaking are likely to occur. 

Placing Concrete, Curing and Cleaning 

As discussed in Section I under the heading of "Sur- 
face," every job specification should require the construc- 
tion complete of a portion of a basement wall or other 
unexposed wall as a demonstration panel using the same 
materials and methods of construction as will be used 
for exposed surfaces. This is so important in obtaining a 
good job that it warrants repetition. The job should not 
be permitted to proceed until an entirely satisfactory 
panel of adequate size has been constructed to serve as a 
criterion for the completion of the job. 

Segregation of the concrete during placing, and splash- 
ing of the forms above the level of the concrete being 
deposited must be avoided. This is best done by requiring 
that the concrete be placed through an "elephant trunk 1 ' 
(a canvas or metal spout), particularly it the concrete 
must be dropped more than 3 or 4 feet. 

In addition to showing the location of construction 
joints on the drawings the manner in which they are 
made should be definitely specified, because the degree 



of perfection of construction joints has a very important 
influence on the appearance of the job. To be sure of a 
straight, flush joint it should be specified that the con- 
crete be floated off to a level line, and bolts should be 
provided about 3 in. below the joint with which the 
forms above can be drawn tightly against the already 
hardened concrete. 

Curing is a most important operation in all concrete 
work. The strength, imperviousness and durability of 
concrete is to a large extent dependent upon adequate 
curing. Architectural concrete should be kept thoroughly 
wet for at least 5 days unless high early strength cement 
or concrete is used, when a minimum of 2 days' curing is 
adequate. Wet curing means soaking wet continually. 
The specification should definitely require it. 

There should be no honeycomb, sand streaking or other 
imperfection in an architectural concrete job if the work 
is done in accordance with the specification just outlined. 
There will, however, be tie holes to be plugged and if 
there is an occasional small imperfection which the 
architect will permit to be patched, it should be done in 
strict accordance with a carefully written specification. 
Mortar for patching must match the color of the con- 
crete, which will require the use of some white cement, 
otherwise the patch will be considerably darker than the 
surrounding concrete. It should be required that a test 
patch be made and allowed to harden and dry out to 
determine the proportions of the mortar that will have 
a satisfactory color. 

Concrete surfaces, like other masonry construction, 
usually require cleaning as a final operation. Water 
streaks, slight oil stains and accumulated dirt must be 
removed. It should be specified that smooth surfaces be 
washed with a 5 to 10 per cent solution of muriatic acid. 
After the acid has been thoroughly washed from the 



Fig. 22. Big business is often housed in oyie^story buildings which, when well designed and constructed like the Caterpillar Tractor 
Co. salesrooms in Walla Walla, Wash., enhance property values in any city. Harold E. Crawford, architect; E. Mardis, contractor. 





surface, a mixture of one part cement 
and one part sand should be applied as 
a brush coat. After the grout has begun 
to harden slightly, but while it can still 
be scraped off with the edge of a steel 
trowel, any excess grout should be re- 
moved and in about 1 hour the wall 
should be rubbed vigorously with bur- 
lap to remove the grout entirely from 
the surface. The process is primarily a 
cleaning and scouring rather than a 
coating over of the surface. Small air 
bubbles or pits on the surface are filled 
and the wall is left with a clean, uni- 
form appearance. 

The specification for every small 
architectural concrete building should 
include the requirements discussed in 
the foregoing paragraphs*. They are as 
important to secure good results on the 
small job as on the large building. 



For a typical specification see ''Concrete 
Information — Architectural Concrete Spec- 
ification — AC- 1 . ' * 



Fig. 23 . Well-proportioned design and good 
construction combine to make even the small- 
est commercial buildings valuable assets to 
any community. The Bank, Williston, Fla., 
designed and built by J, B. McLeod, is an 
example. 



Fig. 24. Qarages are utilitarian structures 
that frequently have been sorely neglei 
architecturally. These views of the Oregon 
Motor Stages Co. bus storage terminal and 
office in Portland, Ore., designed frv Knighton 
and Howell, architects, show that such build- 




ings may be made most attra< 
The close-up showing the si 
dash finish on the concrete walls 
s hous also the workmanlike 
cutwn of all the details by I 



Fig. 2$. In the jail ad- 
dition to the court 
house in Laurel, 
\fiss., Overstreet and 
Town, architects in 
Jackson, made use of 
an effective ornament- 
al motif at each side of 
the entrance which 
was readily formed 
with waste molds. I. 
C. Qarber and Sons, 
fackso)i, jvc re the 
tr actors. 




SECTION III -CONSTRUCTION 



Forms 

AN architectural concrete building is no better than the 
Y\^ forms in which the concrete is placed. When the 
forms are removed the quality of the job is revealed. 
Assuming that the concrete mix is properly designed and 
has been placed with care, the character of the finished job 
depends entirely upon the form construction 

When concrete served only as a structural material, the 
architect did not concern himself with the quality or the 
formwork. and the contractor was interested only to the 



point of making forms strong enough to withstand the 
pressure of the concrete. With Jin architectural concrete 
job, the architect should know how the forms arc to be 
constructed and of what materials, just as he knows the 
texture, color and quality of the brick and the width and 
type of mortar joints to be used in a brick masonry job 
Although the forms do not remain as a part of the finished 
wall, their lasting impression is left in the concrete so, in 
effect, the forms of an architectural concrete job are after 
all a component part of the finished product. 

Just as it is important to build structural concrete forms 




Fig. 26 \ 
variel hittc* 

turd I styles arc 
d in United 
Post Office 
buildings executed 
hitectural con- 
crete I he one at 
Luting, Texas, it as 
the 
Treasury Depart- 
meat and built by 
Algernon Blair, 
contractor, Moyxt- 
gpmery, Ala 



Page 17 




Fig. z 7 . The quality of food and service offered at Yaw's Top Notch Restaurant, Portland, Ore is proclaimed fry the 



strong enough to withstand the pressure of the concrete, it 
is doubly so tor an architectural concrete job, because a 
little deflection or bulge in a column or beam may be 
covered up if some veneer is used, but where the concrete 
is to be left exposed, bulges and irregular lines cannot be 
tolerated. The contractor should design his forms just as 
any other structure is designed to carry load or resist 
pressure, and the architect should pass upon and approve 
the contractor's form details the same as shop drawings 
for structural steel, cut stone or any other material that 
must be detailed. 

The contractor will find it to his advantage even on the 
small job to study the job and lay out an appropriate 
plant. Money can be saved by doing as much work as 
possible on the ground in a small mill set up alongside the 
building. This does not mean that the forms should be 
made into panels which arc set in position to make up the 
wall forms. Prefabricated panels should be used only 
where a single panel will cover an entire surface between 
reveals or openings so that a joining between panels will 
not be nccessarv. 

The specification should require the kind and quality 
of sheathing material to be used, but if it does not, the 
contractor should, in the interest of economy and the 
quality of the finished job, use only the best grade of mate- 
rial required for the type of surface desired. The use of 
second-grade lumber, or plywood or Presdwood not made 
specifically for concrete forms, will lead to greater rather 
than less cost because of few reuses, and the quality of the 
work will be unsatisfactory. 

Craftsmanship is essential in architectural concrete 
form building. Lines must be level and plumb. Joints 
must be made tight and corners locked so there will be 
no movement and leakage. Stone pockets and ragged 
rough arrises result from leaky forms which can be avoided 
by attention to well-established principles of form con- 
struction, which are the same for every job, big or little 



Careful inspection of the forms is important. The exte- 
rior face form should almost invariably be constructed 
first. In this way, before the reinforcing is placed and the 
inside form constructed, the architect can inspect the 
forms carefully to be sure they are constructed as desired. 
If there arc poorly-made joints, sheathing boards with 
loose knots, boards that are warped and cupped, or any 
other imperfections apparent in the forms at this stage of 
the job, they should be immediately corrected because 
such imperfections will mar the final appearance of the 
building. 

The subject of form construction for architectural con- 
crete buildings has been discussed thoroughly in the book- 
let "Forms for Architectural Concrete' which can be had 
upon request to the Portland Cement Association. Refer- 
ence should also be made to the plates on pages 22 to 35 
of this booklet for illustrations of proper form details. 
The forms for practically every essential part of a building 
are shown, including forms for special decorative details. 

Reinforcing 

It is sometimes thought that the reinforcing required in 
the walls of a small building should be less in proportion 
to the cross-sectional area of the concrete than in a larger 
building. This is an entirely erroneous conception The 
reinforcing provided in the walls of an architectural con- 
crete building is for the purpose of resisting stresses 
created by volume changes due to temperature and shrink 
age. 1 hese forces will be virtually the same, regardless of 
the size of the building. The table on the next page shows 
the minimum amount of reinforcing that should be used 
in any building. 

It should be noted that the size and spacing of bars is 
dependent upon the thickness of the wall and not upon its 
over-all dimensions. Small bars are recommended for 
wall reinforcement because of the greater surface area in 



Page 



proportion to the cross-sectional area, insuring the maxi- 
mum bond between bars and concrete. Another advantage 
in using small bars is that a better distribution is possible. 



TABLE I 



Wall u , 
_. , Horizontal 

, . Kcimorccment 
Inches 


Vertical 

Reinforcement 


6 


:i g in. rd. ac 8-in. ccrs. 
in center of wall 


%-in. rd. at S-in. ctrs. 
in center of wall 


8 


%-in. rd. at 6-in. ctrs. 
in center of wall 


%-'\n. rd. at 8-in. ctrs 
in center of wall 


i i 


j^g-in. rd. ac l o in. ctrs. 
in both faces of wall 


%-in. rd. ac 12-in. ctrs. 
in both faces of wall 


1 2 


%-in. rd. at 8-in. ctrs. 
in both faces of wall 


%~in. rd. at 12-in. ctrs. 
in both faces of wall 



Wire mesh made especially for concrete reinforcement 
may be used in place of bars. Chicken wire, woven fencing 
and mesh of that type is not suitable for concrete rein- 
forcement. 

There arc places ol critical stress in a building wall 
which require more than the normal amount of reinforc- 
ing shown in Table I. It has been found from experience 
that the parapet, for example, should have about 50 per 
cent more reinforcing than the wall below the roof And 
it is especially desirable to place two or three "' g-in. 



round bars completely around the parapet at the coping 
line.* 

The top and bottom of spandrels should also be pro 
vided with two or three fairly heavy bars, whether or not 
required for structural strength. Likewise, the corners of 
openings must be specially reinforced to resist the stresses 
concentrated there by the presence of the hole in the wall. ** 

Placing reinforcing so it is securely held in position is 
important. This must be done without driving any nails 
into the outside forms or otherwise providing a fastening 
that would mar the finished surface. The curtains of bars 
can be held away from the exposed face by tying them 
back to the inside form. Individual bars should be 
securely wired together to prevent displacement while 
placing concrete. ** 

Concrete 

Strength was at one time considered the principal re- 
quirement of structural concrete It is a factor ol real 
importance in any concrete construction, but not the most 
essential quality in architectural concrete Actually, the 
strength required in the walls ol a small building or even 
a large one is not particularly high With present 
cement and modern methods ol construction, adequate 
strength could he secured with a water cement ratio thai 
* Sec ( 



Fig 28 Service stations must often he located in residential sections \ttractive structures like this Shell Oil 
Company station in Spokane t U t ;s/* , will not he resented A\ neighbors, \//":< re the bu\ 




Page 19 




Fig. zg. A mod- 
est structure of 
modern lines de- 
pending upon 
grilles and rusti- 
cations to relieve 
large areas of 
plain walls, the 
Huff Theater, 
Coeur d'Alene, 
Idaho, ivas de- 
signed by Bjarn 
Moc t architect in 
Seattle. Qeorge 
Battler was the 
contractor. 






■ int 
all 
i ,11 « Lthsi 

■ 

:tcn 

CC made 

an architectural 

iring 

the 

>ntaimng an 

laterial r 

sand st r 

int archi- 
.. difficulties It simplv 



/ wring 

like solid brick masonry, is a relatively good 
luctot of heat, making it necessary to fur archil 
tural concrete avails of buildings In the north Furring 

minimizes heat loss dnd prevents condensation ol air 

borne moisture 

The amount of furring required depends upon the 

chid tea wall and various atmosphi 

iitions Tables giving the relative values ol diffd 
of furring arc available M 
application of furring t ills will dt : 

upon the type used. There us kinds of insulating 

1 as a form liner against whit ! 
i When the for 
insulation remains bonded to the 

1 as a plaster bas< iarh 

and [ hollow 1 for fun 

it is secured | furring 

• 



' 









■^ 




=i r 




JL 



J 



Form D etails - Layouts 



CITIZEN'S NATIONAL 
BANK 

COLTON, CALIF. 

G.STANLEY WILSON, ARCHITECT 
BAKKER&ROBINSON.CONTRACTORS 




FORM DETAIL FOR, 
FLUTED PILASTERS 



Page 22 







^r 



3 






DECKER BUILDING 

JUNEAU, ALASKA 

N.LESTER TROAST AND ASSOCIATES. ARCHITECTS 
WARRACK CONSTRUCTION CO., CONTRACTOR 




I 






"! 












1 



SHI] 



■ LINE OF WINDOW JAMB AbOVE 



ELEVATION 




-HHHi 



ELEV4TION 



WALL SECTION 
ABOVE SHOW WINDOW 



DECORATIVE BAND 
ABOVE SHOW WINDOW 



Pa^c zj 








SUNIL/Wtr § 

-a 





™ NITURE S ^(LA» J^ 






WASTE v 



SUPPORTING MOCJ^ 










. 






o 






v^-l 



NATIVE 
i&OVE Pfir 



SUNILAND FURNITURE CO. 

HOUSTON, TEXAS 

BURNS ROENSCH, ARCHITECT 

DON HALL, CONTRACTOR. 



Jl 



*=? 



' 



I~~I 







■IB— HT 

____ I 

CROSS SECTION 
; 'J PILASTER 



. 




PARAPET ABOVE DOOR 

fr — 



FIRST FLOOf^' 






■ q . :<i* .9' 



SILVER CREEK 
RURAL SCHOOL 

FAIRBURY.NEB. 

W.P. A. PROJECT 

C.L.M C - PHILIPS. 
ARCHITECT 



4 




FORM DETAIL 
CENTER. LINE OF FRONT 



w 1 





■jjJ 



3G-G 



FULL SIZE DETAIL 
OF WATER TABLE 



FULL SIZE DETAILOFV-STRIP 
AT TOP & BOTTOM OF WINDOW? 




IFOM 



Page 25 



SAME- AS 
SPANDRE 

DT-TAIL 







J 

'A 









-. : 






__ Wt 



» 



■:,*: 



i^EJ* 



RICHMOND SAND 
& GRAVEL CORP. 

RICHMOND, VA. 

EDWARD F. SINNOTT. 
ARCHITECT 

JAMES FOX & SONS 
CONTRACTORS 






■ 






y.^ : *A 






SECOND STORY WINDOW HEAD 








1 


! 




fct- 


<• 




O 








'- C! 


EAT iv di 






^^^^ 


5] 
CC 


T AFTFK 
MCRETE IS 






Jnp 


PL 


ACEDTO 








TN 


IS POINT 






> 









VNDOWblLL 
HI T HRU SPANDREL 

; 



' 












j 











WINDOW JAMB 



SECOND FLOOK 







FTEK 

ED TO 



L FORMS 




!f>LE 




FIRST FLO' 



Page 26 




HOLMES COUNTY JAIL 

LEXINGTON, MISS. 

OVERSTREET AND TOWN , ARCHITECTS 
CURRY AND CORLEY, CONTRACTORS 



*a 



A 



& 



v. 



.■(V --o.-x); 






. 



X 



:-2,; 



X\ ' : ' -Vj"."." & 

9 .rfi 



3BS5 / 



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tf*tfi9i 



Cv 



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■°''. ;;■::• 

O o 

■.■;°'C- 



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6 




22 



S 



■*■ 



fr 



— b» 



DETAIL OF CORNER 



HEAD OF SECOND STORY WINDOWS 
BETWEEN ROUND BULLIONS 




SILL OF SECOND STORY WINDOWS 
SHOWING ORNAMENTED SPANDREL 



A. 






ZKZ 



1 






t 







CROSS SECTION OF ROUND MULLIONS fc SPANDREL 



PdgC 27 




RAOLET-na 
TO INSIDE 
OF FORM 



.mm. &* 



MUNICIPAL JAIL 

LYNCHBURG, VA. 

HINNANT AND SMITH, ARCHITECTS 
JOHN MILLER,, CONTRACTOR 




—I I— < 






zv 



1 



_Jj 

Eh 










-4m 






— 



-£* 1 




1 ^ >~» ^N 









~w 



TTI 



m 



FACE LINE 
OF PILAf-TER.- 



^ L LINE 



+■ 






~yj _____ 



OF WATER TABLE 




FORM FORPILASTERWITH V- FLUTINO SECTION THRU WATERTABLE 



SECTION ON CENTER LINE 
THRU FRONT OF BUILDING 



Page 2.S 



ASSOCIATED 
TELEPHONE 
COMPANY 
LIMITED 

ONTARIO, CALIF. 

MAURICE SASSO 
STRUCTURAL ENOR. 

CAMP5ELL CONST. 
CO., CONTRACTOR. 




V/EIOHT OF THIS PANEL TO BE 
CARRIED ON FORMING FOR. 
PIER AT SIDE 



FORM DETAILS FOR 
WASTE MOLD ORNAMENT 
OVER DOORWAY AND 
PARAPET WALL AbOVE 



' 



\7~ 



■ 
















s ■ >,• 










. 






■o 



! 

■ 



' ! 









:TAIL FOP. 
CORNER PILASTERS 






" '■ i. • . ■ — — - ~ — . J^r~*^\ — ^. 






^r 






o--:->:" 



?~a 



TT 



DETAIL OF FLUflNGS IN 50TH 
PILASTERS AND PAKAPET 



lJ age 19 




THIS SECTION OF FORM TO BE 
FITTED AND THEN LAID ASIDE 

• EKMIT PLACING OF CONCRETE 
IN WAIL BELOW-SET IN PLACE 
AFTER, SLAP. IS PLACED- 



LABORATORY AND OFFICE 
SEWAGE TREATMENT PLANT 












Ob, 



4§ 



• 




















■ 





FIRE STATION 

HOUSTON, TEXAS 

JO M C KENZIE, ENGINE 
5ACE CORP.. CONTRAC1 




■It i 

III ii 




• 



H 






*«}■ 



: m 



S& 















1 



— 
























AND ET 



Page 3 i 











SERVICE STATION 
CONTINENTAL OIL COMPANY 



HOUSTON, TEXAS 

W.R. BROWN. ARCHITECT 
L.R.ASHMORE, CONTRACTOR 




FLOOR PLAN 



VERTICAL SECTION 
SHOWING DECORATIVE 
PANEL ABOVE 
DOOR OPENING 



DETAIL SHOWING 
INSTALLATION OF 
OVER HEAD DOOR. 




m 



^ 



A. 



" O 0;.o«- 









a..-. 



. . ■ 






^^-. 



__ 






PLASTER. FK 
MOLD— 









T" 



FLUTINOS IN PARAPET 
FORM DETAIL ABOVE LARGE DOOR 






SERVICE STATION 
CITIES SERVICE 
OIL COMPANY 

EL RENO.OKLA. 

DESIGNED BY CITIES SERVICE 
OIL COMPANY 

CONNELLY CONSTRUCTION CQ 
CONTRACTOK 










I" ■ i 

■ -I 



Sz 



W 



I 






■ > 'i 



- 



— i 

■ 




COM Elk DETAIL 



OFFICE ENTRANCE DETAIL 



P>iK< .3.3 




NASSAU CO. ROAD 
DEPT. GARAGE 

HEMPSTEAD, N.Y. 

W.RA.PROJ r 
DE? 






■ 













.'■WW 



- 



USTUC ENING DETAIL OF CANOPY AND WALL ABC 




BATH HOUSE 



SPRINGFIELD, MO. 

EARL HAWKINS. ARCHITECT 

W.W.JOHN50N. ENGINEER. AND CONTRACTOR 





PARAPET AND CANOPY 
■ R ENTfUN 

-4== 






T~ 

- 



P^ 



CROSS SECTION OF SPANDREL 
OVER DOOR 




^TOPAND 60TTOM PLATE CUT TO IUDIUS TO HOLD STUDS TO PROPER LINE 

-SEND 4 THICMESSESOF IVG'TO STUDS ONE AT * TIME IFTER.5TUD5 HAYE U :EFO.^ 

SHEATHING IS APPLIED- CONTINUE SHEATHING AMD WALES PAST OPENINGS IN Cl^CULAK 

WALLS TO HOLD TO LINE 

CROSS SECTION THROUGH TYPICAL WALL FORM 



Page $5 




Fig- 33- Wolfermans — "Qood Things to Eat" Kansas City, Mo., Edward W Tanner, architect; Long Construction Co., contracts 



"In architecture, as in nthpr arts, two considerations 

must be constantly hept in \it>\\; namely, tbe intention, 
and tbe matter used ta express that intention/' — \ item ins 



PRINTED IN 



T-27— -